The present invention relates, in general, to drug delivery, and in particular, to a new and useful device for delivering drugs to the body of a patient at a very low fluid flow rate. The present invention also includes the method of manufacture of the novel drug delivery device.
Fluid delivery devices, and particularly, drug delivery devices are known. Additionally, it is also known within the fluid delivery or drug delivery field, that fluids, such as drugs, can be moved through helical flow paths. For example, U.S. Pat. No. 3,998,244 (Bentley) describes a drip irrigation valve with a helical flow path for the delivery of various agricultural liquids, such as fertilizers to be fed through an irrigation system. This particular system is useful for providing drip irrigation that conserves water, minimizes weed growth and facilitates the transport of the agricultural liquids through the irrigation system.
U.S. Pat. No. 4,176,683 (Leibinsohn) describes a flow regulator useful in apparatus designed for administering liquids to the body. The device is a presettable fluid flow regulator having an elongated sleeve of flexible material and a core within the sleeve having a helical recess of varying cross section carved or scored into the core. A ring on the outside of the sleeve has an internal diameter slightly less than the outer diameter of the sleeve and is used to squeeze the sleeve against the core to define a flow passage between the core and the sleeve. The volume of flow is determined by the longitudinal position of the ring along the sleeve.
U.S. Pat. No. 6,270,483 (Yamada et al.) describes a liquid discharge regulator and a liquid feeder that utilizes a liquid discharge regulator. The regulator has a channel spirally carved or formed on the surface of a passage forming member. The surface of the passage forming member is brought into close contact with the inner surface of a housing part wherein the channel functions as a liquid passage. The passage forming member is made of a plastic material by using injection molding manufacturing and mass production. The main purpose behind using the plastic material made exclusively through the injection molding process for the formation of the passage forming member is aimed at reducing manufacturing costs of the regulator.
U.S. Pat. No. 5,985,305 (Peery et al.) describes a back-diffusion regulating outlet consisting of a male threaded member in threaded relationship with a smooth interior surface of a reservoir thereby forming a helical flow path. As clearly shown, similar to the other prior art flow regulator devices, the regulating outlet consists of a solid core of material which serves as a male threaded member, i.e. a screw, that is in mating relationship with the smooth interior surface of the reservoir.
To date, there have been no fluid flow regulator devices, mechanisms or drug delivery devices using these type of mechanisms that can be provided or manufactured in an extremely efficient manner, easily and readily adaptable to any desired designed configuration, and having extremely low cost of manufacturing.